Apparatus for drying fuel.



a. HERMANSENf APPARATUS FORDR YING FUEL. APPLICATION FILED SEPT-25,1913.

Patent meb. 29, 1916.

" 2" SHEETS-SHEETTQ H. HERMANSEN. APPARATUS FOR DRYING FUEL. n APPLICATION FILED SEPT.'25, 1913. l'zg glg I Patented Feb 29, 1916.

2 S'HEE S-SHEE] 2- A I v I I of internal firing there is some danger of ex-' apparent from taken 1n connection with the accompanying UNITED STATES rarrnrrr orFIoE.

HERMAN HERMANSEN, O1? BAYBRIDGE, OHIO, ASSIGNOR '10 SANIDUSKY PORTLAND CEMENT COMPANY, OF BAYIBRIDGE, OHIO, A CORPORATION OF OHIO.

APPARATUS FOB. DRYING FUEL.

Specification of Letters Patent. Patented Feb.29, 1916.

Application filed September 25, 1913. Serial No. 791,795.

dent of Baybridge, in the county ofErie;

State of Ohio, have invented certain new and useful Improvements in Apparatus for Drying Fuel, of which the following is a specification.

This invention relates to an improved apparatus for drying coal or other fuel with arrangements for coyering and utilizing the combustible dust ordinarily lost in fuel drying operations.

The novel features of the invention will be he ollowingdescription,

drawings.

In the drawings, Figure 1 is a side view of an apparatus embodying my invention; and Fig. 2 is a similar view showing a slightly modified construction.

The drying of fuel is ordinarily. carried on inrevolving cylinders, heated either internally or externally. In this operationa considerable amount of dust is always formed by the agitationof the fuel. In case plosion of this dust by Eontact with the fire gases, and the strong current of gases through the drier carries the dust into-the atmosphere, causing loss and nuisance. This latter objection is also met with in the case of external'heating, as it is necessary to provide for circulation of air through the drier to carryofi' the moisture evolved from the fuel, and this current of air also carries away a large amount of dust. It is also well -known that external heatingisvery inefficient, being wasteful. of heat. I have fourid it possible to overcome all these obstacles and to carry on the drying of fuel safely, economically, and without loss of dust, in an internally fired revolving drier, by 1) employing means to cool the fire gases before they enter the drier to a point below the temperature .of ignition of coal dust, by causing the fire-gases to pursue an elongated path and by mixing cool air with .the gases, and (2) by drawing the dusta laden gases, as they. escape from the drier, through a fan and forcing them into furnaces, where they serve the purpose for which an air blast is ordinarily employed, to atomize and diffuse additional fuel in pulverized form". In this way the dust car front of the furnace.

ried by the gases is burned and fully utilized, instead of being discharged as an objectionable eflluent' into theatrnosphere. It is well. known that in the ordinary process of coal dust burning in furnaces and kilns, as largely employed in manufacture of cement and other products, theair which is blown in with the fuel. is only a small-part of that required for combustion, the balance of the air required being drawn in by the stack draft through openings in the The substitution of a blast of fire-gases containing more or less excess of air for the air blast commonly used, therefore, has no notieeableinjurious eifect upon the combustion in the furnace, while the heat of the gases and the combustible dust which they carry .produces a marked economy in fuel used.

In Fig. 1 ofrthe accompanying drawings,

I have shown a revolving cylindrical drier v 1, which communicates at one end with the combustion chamber 2 and which extends fire is maintained on the grate 7 air being admitted above the grate through the door 8 in regulated quantities and the fire-gases pass around the arches 9, 10, which serve to so lengthen thepath of the gases that they are cooled to, a point where they will not ignite the combustible dust in the cylinder 1. They will however be sufiiciently hot to internally heat that cylinder and dry the ,fuel therein and it will be observed that in this form the gases move down the cylinder inthe ,same direction as that followed by the coal or other fuel. The coal is discharged at the lower end of the cylinder through the outlet 11 and the fire-gases now carrying. a considerable amount of dust picked up within the cylinder 1 pass to the stack 12 and if desired they may be allowed ing the damper 13. In normal operation however the gases carrying the dust are drawn down through the pipe 14 by the fan .to escape from the top of that stack by open- 15 and are forced along apipe 16 extending in front of the furnaces l7 and having branches discharging into those furnaces. The dust-laden gases discharged into the furnace assists the combustion, and pulverized fuel contained in the hoppers 18 may be led down through the pipes 19 so as to outlet valve 13, it will be understood that this is not necessary but that the gases may be conveyed directly by means of the fan to the furnacc. This stack serves a useful purpose in ca of interruption to the operation of the fur ace or the fan, being used at that time as a onvenient exit for the gases.

In Fig. 2 I have shown a construction similar to that illustrated in Fig. lcxcept that the revolving cylinder 1 is inclined upwardly from the combustion chamber 2 and the fuel l\ fed into it at the opposite end and is discharged at the end next to the combustion chamber. In this case the scrcawconveycr 21 which receives the fuel from the hopper 5 leads into the elbow at the bottom of the stack 12 and consequently the. coal passes down the cylinder 1 to the discharge outlet :22 while the fire-gases from the combustion chamber pass up along the cylinder in the opposite direction from the movement of the fuel. The construction of the parts for utilizing the dust-laden gases in the furnaces is the same as that shown in Fig. 1.

Having thus described my invention, what I claim is:

1. A fucl drier consisting of an internally heated revolving cylinder. an exit pipe, exhaust fan and delivery pipe for conveying dust-laden gases from drier to furnaces. and means for supplying pulverized fuel to the gases as they enter the furnaces, all substantially as shown and described.

- 2; A fuel drier consisting of an internally heated revolving cylinder, means for feeding raw fuel to drier, an exit pipe, exhaust fan and delivery pipe for conveying dustladcn gases from drier to furnaces, and means for supplying pulverized fuel to the ga as they enter the furnaces, all sub stautially as shown and described.

drier consisting of an internally ii. A. fuel licatcd revolving cylinder, means for feeding raw fuel to drier, a fireplace for heatmg drier, an exit pipe, exhaust fan and delivery pipe for conveying dust-laden gases from drier to furnaces, and means for supplying pulverized fuel to the gases as they enter the furnaces, all substantially as shown and described.

4. 'A fuel drier consisting of an internally heated revolving cylinder, means for feeding raw fuel to drier; a fire-place for heating drier, arches in fire-place to cause products of combustion to traverse an elongated path, an exit pipe, exhaust fan and delivery pipe for conveying dust-laden gases from drier to furnaces, and means for supplying pulverized fuel to the gases as they enter the furnaces, all substantially as shown and described.

5. A fuel drier consisting of an internally heated revolving cylinder, means for feed ing raw fuel to drier, a fireplace for heating drier, arches in fire-place to cause prod ucts of combustion to traverse an elongated path, openings in fire-place to admit additional -air to the products of combustion, an exit pipe, exhaust fan and delivery pipe for conveying dust-ladcn gases from drier to furnaces. and means for supplying pulverized fuel to the gases as they enter the furnaces, all substantially as shown and described.

6. In an apparatus of the class described. the combination of an inclined rotatably mounted cylinder. means for feeding raw fuel to said cylinder. a combustion chamber connected with one end of said cylinder, a fire-place in said chamber. arches in said chamber between said cylinder and fire-place to cause products of combustion to transverse an elongated path, the wall of said combustion chamber having an opening therein between said arches and the the place to admit additional air to the products of combustion, an outlet at the lower end of the cylinder. a stack at the end of the cylinder opposite the combustion chamber, a damper controlling the flow of gas through said stack, a furnace. an exhaust fan for withdrawing dust laden gas from said stack and delivering the same to said furnace, and means for supplying pulverized fuel to the gases as they enter the furnace, substantially as shown and described.

In testimony whereof I aiiix my signature in presence of two witnesses.

. HERMAN l-IERMANSEN. 

